CADMIUM IN SOILS AND PLANTS

Transcription

1 CADMIUM IN SOILS AND PLANTS

2 Developments in Plant and Soil Sciences VOLUME 85

3 Cadmium in Soils and Plants Edited by M.1. McLAUGHLIN CS/RO Division of Soils/CRC for Soil and Land Management. Gien Osmond. Australia and B. R. SINGH Department of Soil and Water Sciences. Agricultural University o{ Norway. Norway SPRINGER SCIENCE+BUSINESS MEDIA, B.V.

4 A c.i.p. Catalogue record for this book is available from the Library of Congress. ISBN ISBN (ebook) DOI / Prillled on acid-free paper All Rights Reserved 1999 Springer Science+Business Media Dordrecht Originally published by Kluwer Academic Publishers in 1999 Softcover reprint of the hardcover I st edition 1999 No part of the material protected by this copyright notice may be reproduced or utilized in any form or by any mcans, clectronic or mechanical, including photocopying, recording or by any information storage and retrieval system, without written permission from the copyright owner.

5 This book is dedicated to the memory of Kevin George Tiller

6 Contents Contributors Forewood Preface xi xiii xv 1. Cadmium in Soils and Plants M. J. McLAUGHLIN and B. R. SINGH 1. Introduction 2. Accumulation of cadmium in soils and plants 3. World fertiliser supply - cadmium issues 4. Re-use of waste materials - cadmium issues The Environmental Chemistry of Cadmium S. J. TRAINA 1. Basic chemical properties Aqueous complexation Abundance and form in natural environments Cadmium concentrations in soils Analytical approaches for cadmium speciation in the environment Conclusions 33

7 viii 3. Chemistry of Cadmium in Soil Solution P.A.HELMKE 1. Introduction Properties of cadmium Cadmium in soil solution Measured and calculated speciation of cadmium in soil solutions Phenomena controlling the concentration of cadmium and zinc in soil solutions Conclusions Solid Phase Cadmium and the Reactions of Aqueous Cadmium with Soil Surfaces T. H. CHRISTENSEN and P. M. HAUNG 1. Introduction 2. Solid phases 3. Adsorption-desorption processes 4. Conclusions Anthropogenic Additions of Cadmium to Soils B. J. ALLOWAY and E. STEINNES 1. Introduction 2. Cadmium concentrations in soils 3. Anthropogenic sources of cadmium 4. Conclusions Mechanisms of Cadmium Uptake, Translocation and Deposition in Plants R. M. WELCH and W. A. NORVELL I. Introduction 2. Availability of cadmium in soil 3. Uptake of cadmium by roots 4. Transport and deposition 5. Bioavailability of cadmium in plant foods 6. Conclusions

8 ix 7. Management Factors which Influence Cadmium Concentrations in Crops C. A. GRANT, L. D. BAILEY, M. 1. McLAUGHLIN and B. R. SINGH 1. Introduction 2. Site selection 3. Crop selection and cultivar development 4. Fertiliser management 5. Soil ph and liming 6. Other soil amendments 7. Irrigation water quality 8. Phytoremediation 9. Other management factors 10. Conclusions Adverse Effects of Cadmium on Soil Microflora and Fauna S. P. McGRATH 1. Introduction 2. Data sources 3. Effects on microbes and microbial processes 4. Evidence from field experiments 5. Effects on earthworms 6. Other invertebrates 7. Comparison with Dutch soil quality values 8. Conclusions Soil Cadmium as a Threat to Human Health R. L. CHANEY, 1. A. RYAN, Y-M. LI and S. L. BROWN 1. Introduction Diagnosis of human cadmium toxicity Interpretation of epidemiological survey data Reducing cadmium levels in crops Have crop cadmium levels increased over time? Common errors in evaluation of plant absorption of soil cadmium Livestock food-chains usually exclude cadmium effectively High risk crops 243

9 x 9. Reducing food chain cadmium risk 10. Research on food-chain cadmium risk is still needed 11. Does ingested cadmium increase cancer risk? 12. Conclusions Cadmium in Soils and Plants B. R. SINGH and M. J. McLAUGHLIN 1. Introduction 2. Cadmium in soils 3. Cadmium in plants 4. Adverse effects of cadmium on biota and human health 5. Knowledge gaps and research priorities Index 269

10 Contributors Prof. B J Alloway, Department of Soil Science, The University of Reading, PO Box 2333, Reading RG6 6DW, England, UK. Dr L D Bailey, Agriculture and Agri-Food Canada Research Centre, Brandon, MB, Canada R7A 5Y3. Dr S L Brown, Environmental Chemistry Laboratory, USDA-ARS, Beltsville, MD 20705, USA. Dr R L Chaney, Environmental Chemistry Laboratory, USDA-ARS, Beltsville, MD 20705, USA. Prof. T H Christensen, Department of Environmental Science and Engineering, Technical University of Denmark, DK-2S00 Lyngby, Denmark. Dr C A Grant, Agriculture and Agri-Food Canada Research Centre, Brandon, MB, Canada R7 A 5Y3. Prof. P A Helmke, Department of Soil Science, University of Wisconsin Madison, Madison, WI , USA. Prof. P M Huang, Department of Soil Science, University of Saskatoon, Saskatoon, Canada S7N 5AS. xi

11 xii Dr Y-M Li, Environmental Chemistry Laboratory, USDA-ARS, Beltsville, MD 20705, USA. Prof. S P McGrath, Soil Science Department, IACR - Rothamsted Experimental Station, Harpenden, Hertfordshire AI5 2JQ, UK. Dr M J McLaughlin, CSIRO Land and Water, PMB 2, Glen Osmond, SA 5064, Australia. Dr W A Norvell, USDA-ARS, U.S. Plant, Soil & Nutrition Laboratory, Tower Road, Ithaca, NY 14853, USA. Dr J A Ryan, US Environmental Protection Agency, Cincinnati, Ohio, OH 45224, USA. Prof. B R Singh, Department of Soil and Water Sciences, Agricultural University of Norway, 1432 As, Norway. Prof. E Steinnes, Department of Chemistry, Norwegian University of Science and Technology (NTNU), N-7055, Dragvoll, Norway. Prof. S Traina, School of Natural Resources (Food, Agric & Environ Sci), Ohio State University, Columbus, OH 43210, USA. Dr R M Welch, USDA-ARS, U.S. Plant, Soil & Nutrition Laboratory, Tower Road, Ithaca, NY 14853, USA.

12 Forewood Growing concerns about cadmium contamination of soils and food-chain transfer have prompted great debate about how to reduce human and environmental exposure to cadmium. While potential risk to human health is undisputed, media coverage of this issue has lead to public confusion and undue fear about food safety. The global scientific community has been working hard to address issues related to cadmium in the environment. Much research has been completed and reported in a variety of forums. This book represents a state-of-the-art review of cadmium in soils and plants. It culminates the proceedings from the "Kevin G. Tiller Memorial Cadmium Symposium"; an international symposium held in Berkeley, California, June 24, 1997 that brought attendees from over 41 countries. This publication brings forth new information for scientists, agronomists, and fertiliser manufacturers and summarizes valuable information for policymakers and administrators. The world fertiliser industry has been keenly interested in this issue, has actively supported cadmium research, and has participated in forums and workshops discussing cadmium risk management. The fertiliser industry recognizes that phosphorus fertilisers contribute to the anthropogenic input of cadmium to agricultural soils, along with manure, biosolids and atmospheric deposition from incineration of town wastes, non-ferrous metal production, iron and steel production and fossil fuel combustion. Cadmium occurs naturally as a minor constituent of phosphate rock ore and varying amounts are transferred to the phosphorus fertilisers during the manufacturing process. Technologies to remove cadmium from phosphorus fertilisers are being developed and evaluated, but none are presently economically viable on a commercial scale. Increasing production costs of xiii

13 xiv phosphorus fertiliser is a concern of all farmers. In many developing countries, the use of phosphorus fertilisers is already much too low and increased fertiliser costs would only aggravate the endemic food production problem. Some countries have applied limits to the cadmium content of phosphorus fertilisers, but this can only be achieved by using low cadmium phosphate rock. This approach can not be widely adopted because world deposits of low cadmium phosphate rocks are limited and can only meet a fraction of the world's phosphorus demands. Restricting production to low cadmium phosphate rock or cadmium removal during processing will increase the cost of the fertiliser, which undoubtedly will have important implications for food production, especially in developing countries. It would also have detrimental consequences to the economies of phosphate rock producing countries, many of which are developing countries whose economies rely heavily on phosphate rock trade. Fortunately, other management alternatives are available. Numerous factors affect cadmium behaviour in soils, and its transfer and availability to plants. Additionally, cadmium transfer from plants to animals and humans is also influenced by many factors. These are discussed in detail in various chapters in this publication. Management options that minimize cadmium concentrations in foodstuffs are outlined and the threat of cadmium to human health is clarified. Cadmium is a naturally occurring element in mineral soils. Background amounts vary depending on geologic parent materials, but soil cadmium concentrations typically are less than 1 mg kg-i. Additions of cadmium from phosphorus fertilisers will ultimately increase background soil cadmium but the build-up of soil cadmium from fertiliser is a long-term process and one which is complicated by the vagaries of individual soil environments. That reality is not meant to excuse or nullify efforts to minimize cadmium inputs where possible. The world fertiliser industry applauds the organizers of the "Kevin G. Tiller Memorial Cadmium Symposium" and the publishers of the proceedings in this book. We feel it makes a valuable contribution to our knowledge and understanding of cadmium and how it can be managed to reduce risks to the health of humans and the environment. Terry L. Roberts Western Canada Director Potash and Phosphate Institute LucM. Maene Director General International Fertilizer Industry Association

14 Preface Over forty years ago, concern was first focussed on cadmium contamination of soils, fertilisers and the food chain. Adverse effects on human health were first highlighted nearly 30 years ago in Japan with the outbreak of Itai-itai disease. Since then, substantial research data have accumulated for cadmium on chemistry in soils, additions to soils, uptake by plants, adverse effects on the soil biota and transfer through the food chain. However, this information has never been compiled into a single volume. This was the stimulus for the Kevin G. Tiller Memorial Symposium "Cadmium in Soils, Plants and the Food Chain", held at the University of California, Berkeley, in June 1997 as part of the Fourth International Conference on the Biogeochemistry of Trace Elements. This symposium brought together leading scientists in the field of cadmium behaviour in soils and plants, to review the scientific data in the literature and highlight gaps in our current knowledge of the subject. This series of review papers are presented here and deal with the chemistry of cadmium in soils, the potential for transfer through the food chain and management to minimise this problem. We hope this information provides a sound scientific basis to assist development of policies and regulations for controlling cadmium in the soil environment. We are indebted to our sponsors, the Fertilizer Industry Federation of Australia, the International Fertilizer Industry Association, Potash and Phosphate Institute, Institut Mondial du Phosphate (World Phosphate Institute) and Norsk Hydro As. for supporting this important symposium and this publication. We are also very grateful to our scientific referees who provided valuable comments and suggestions for the improvement of the chapters: xv

15 xvi A M Bernard, FPC Blarney, G Brummer, W T Buckley, A C Chang, R G Garrett, C Klaassen, L A Sparrow, M B McBride, R G McLaren, D R Parker, A W Rate, A H C Roberts, S Satarug, I Singleton, W W Wenzel and E Witter. We also thank Ms Kelly Dunbar for her excellent assistance in final formatting of the chapters. Finally, we dedicate this book to the memory of Dr Kevin George Tiller, who died in August Kevin worked for more than 40 years in CSIRO Division of Soils at Glen Osmond, South Australia, and became a recognised international leader in the study of trace elements in soil and environmental pollution by heavy metals. Kevin's latter years were focussed on the study of cadmium behaviour in soils, and he provided inspiration for many of the contributors to this volume and to other soil and plant scientists around the world studying the behaviour of heavy metals in the environment. M. 1. McLaughlin B. R. Singh February 1999 m Iiit I r I'.\ I